UVB-regulated gene expression in human keratinocytes. Analysis by differential display.

Abstract

AbstractThe ozone layer of the earth effectively absorbs high-energy solar ultraviolet (UV) radiation below 290 nm. Consequently UVC (100–280 nm) radiation is completely blocked by the upper atmosphere while UVB (from 290–320 ) and UVA (320–400 nm) radiation reaches the earth’s surface (1,2). Of this terrestrial UV light, the midrange ultraviolet radiation (UVB) is the most relevant with respect to physical injury to human skin and causes severe damage, including cutaneous inflammation, immunosuppression, as well as the induction and promotion of cancer (for review, see ref. 3). In searching for the physiological targets of UVB radiation, it is important to note that 99% of this radiation is absorbed within the outermost 0.03 mm of the epidermis (4). Therefore, keratinocytes probably constitute a major cellular target. Early events in the UV response of mammalian cells are the activation of transcription factors such as AP-1 (5–7) and nuclear factor-κB (NF-κB) (6) (see also, Chapter 16, this volume) as well as the initiation of signal-transduction events mediated by tyrosine kinases (8,9) (see also, Chapter 7, this volume). Although there is an increasing amount of information about cellular components that lie both upstream and downstream of these proteins within UV-activated signal-trans ductionpathways, investigations of the response of mammalian cells to UV exposure have mainly been restricted to a small number of known target genes.KeywordsPolymerase Chain ReactionNorthern Blot AnalysisPrime CombinationHaCaT CellDifferential DisplayThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.